network firmware missing on a dell latitude 610

Which Ubuntu release?
Did you verify 'additional drivers'?
Verify if linux-firmware is installed.
What is the exact error message?

I installed Ubuntu 11.10. The error message is "network firmware missing". How do I verify 'additional drivers'? How do I check if linux firmware is installed? Please give me detailed instructions. Thanks

'Additional drivers' are in system-settings which can be accessed from top panel right hand side corner, the small system-tool icon.

Please update the system first, open a terminal: ctrl+alt+t
Enter:
sudo apt-get update
sudo apt-get upgrade
sudo apt-get -f install

In case post error messages, hightlight the terminal output copy&paste it here in message box, thanks.

ubuntu@ubuntu:~$ sudo apt-get update
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric InRelease
Err http://archive.ubuntu.com oneiric InRelease

Err http://archive.ubuntu.com oneiric-updates InRelease

Err http://security.ubuntu.com oneiric-security InRelease

Err http://archive.ubuntu.com oneiric Release.gpg
  Could not resolve 'archive.ubuntu.com'
Err http://security.ubuntu.com oneiric-security Release.gpg
  Could not resolve 'security.ubuntu.com'
Err http://archive.ubuntu.com oneiric-updates Release.gpg
  Could not resolve 'archive.ubuntu.com'
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric/main TranslationIndex
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric/restricted TranslationIndex
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric/main Translation-en_US
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric/main Translation-en
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric/restricted Translation-en_US
Ign cdrom://Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012) oneiric/restricted Translation-en
Reading package lists... Done
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/oneiric/InRelease

W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/oneiric-security/InRelease

W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/oneiric-updates/InRelease

W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/oneiric/Release.gpg Could not resolve 'archive.ubuntu.com'

W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/oneiric-updates/Release.gpg Could not resolve 'archive.ubuntu.com'

W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/oneiric-security/Release.gpg Could not resolve 'security.ubuntu.com'

W: Some index files failed to download. They have been ignored, or old ones used instead.
ubuntu@ubuntu:~$ sudo apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
ubuntu@ubuntu:~$ sudo apt-get install
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
ubuntu@ubuntu:~$

Please open sources.list via terminal:
gedit /etc/apt/sources.list

Copy&paste complete content there
http://paste.ubuntu.com/

and post the link here. Thanks.

ubuntu@ubuntu:~ gedit/etc/apt/sources.list
bash: gedit/etc/apt/sources.list: No such file or directory

Fernando, there is a space between gedit and /etc...
CLI is case sensitive, maybe rather copy and paste a command.

# /etc/apt/sources.list

deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012)]/
oneiric main restricted
deb http://archive.ubunto.com/ubunto/ oneiric main restricted
deb http://security.ubuntu.com/ubunto/ oneiric-security main restricted
deb http://archive.ubnto.com/ubuntu/ oneiric-updates main restricted

My touchpad is frozen. How can I activate it?

If the keyboard still works restart xserver and login again.
First, if possible focus the window and close it with: alt+f4
Then restart xserver (which is like loggin out): alt+print+k

Touchpad freeze may be an issue with the kernel or rather a symptom of missing firmware.

Restarting does not unfreeze the touchpad. I really want to try ubuntu.

Before proceeding the task and these
http://ubuntuforums.org/showthread.php?t=1535575
are the specifications of your Dell, maybe consider to upgrade RAM and grahic card support.

It needs at least 1 GB RAM and a proper graphic card with enabled 3d support to run Unity-3d.
https://wiki.ubuntu.com/DemystifyingUnityGraphicsHardwareRequirements

You could try to login to Unity-2d, try Ubuntu derivatives, e.g. Xubuntu, Lubuntu
https://wiki.ubuntu.com/DerivativeTeam/Derivatives
or read about minimal installation.
https://help.ubuntu.com/community/Installation

If touchpad still doesn't work, you can workaround only with keyboard.

Close open windows with alt+f4.
Reboot with REISUB keys, keep alt+print down and then slowly press one key after the other:
alt+print+r
+e
+i
+s
+u
+b

http://www.ubuntugeek.com/how-to-use-magic-system-request-keys-in-ubuntu-linux.html

Directly after reboot press 'shift' key in order to access grub menu.
Select (with arrow key) and login to recovery mode, which has several options to repair, e.g. packages and xserver.
It also has an option called 'root-shell', which is like a terminal (text mode and no touchpad necessary).
From there apply:
dpkg --configure -a
apt-get update
apt-get upgrade
apt-get -f install

Verify if linux-firmware is installed:
dpkg -l linux-firmware

If it is installed the output looks like this:
ii linux-firmware

If not, install:
apt-get install linux-firmware

Take your time and if possible note error messages. Thanks.